Relationship Between the Kinetic Power and Bolometric Luminosity of Jets: limitation from black hole X-ray binaries, active galactic nuclei, and gamma-ray bursts

The correlation between the kinetic power $P_{\rm jet}$ and intrinsic bolometric luminosity $L_{\rm jet}$ of jets may reveal the underlying jet physics in various black hole systems. Based on the recent work by Nemmen et al. (2012), we re-investigate this correlation with additional sources of black-hole X-ray binaries (BXBs) in hard/quiescent states and low-luminosity active galactic nuclei (LLAGNs). The new sample includes 29 sets of data from 7 BXBs and 20 LLAGNs, with $P_{\rm jet}$ and $L_{\rm jet}$ being derived from spectral modeling of the quasi-simultaneous multi-band spectra under the accretion-jet scenario. Compared to previous works, the range of luminosity is now enlarged to more than $20$ decades, i.e. from $10^{31}{\rm erg/s}$ to $10^{52}{\rm erg/s}$, which allows for better constraining of the correlation. One notable result is that the jets in BXBs and LLAGNs almost follow the same $P_{\rm jet} - L_{\rm jet}$ correlation that was obtained from blazars and gamma-ray bursts (GRBs). The slope indices we derived are $1.03\pm0.01$ for the whole sample, $0.85\pm0.06$ for BXB subsample, $0.71\pm0.11$ for LLAGN subsample, and $1.01\pm0.05$ for the LLAGN-blazar subsample, respectively. The correlation index around unit implies the independence of jet efficiency on the luminosity or kinetic power. Our results may further support the hypothesis that similar physical processes exist in the jets of various black hole systems.Comment: 5 pages, 3 figures, to appear in ApJL, updated versio

NEUROPILIN IN THE VASCULAR SYSTEM: MECHANISTIC BASIS OF ANGIOGENESIS

The vascular system is critical for maintaining homeostasis in all vertebrates. Structural studies of Neuropilin (Nrp), an essential angiogenic receptor, have defined its role in regulating angiogenesis, the formation of new vessels from the existing vasculature. Utilizing biochemical and biophysical tools we describe the ability of Nrp to function as a co-receptor for the VEGFR receptor tyrosine kinase. Two families of Nrp-1 ligands, Vascular Endothelial Growth Factor A (VEGF-A) and Semaphorin3F (Sema3F), physically compete for binding to the Nrp-1 b1 domain, and have opposite roles. VEGF-A is a potent pro-angiogenic cytokine while Sema3F is an angiogenesis inhibitor. Using coupled structural and functional studies, we have discovered the basis for potent competitive binding of Sema3F to Nrp1 requires engagement of two distinct binding sites. These data provide a basis for understanding the rational design of novel high affinity Nrp-1 inhibitor

Glycosylated Collagen Interaction with Cells Through DDRs and Integrin

https://openworks.mdanderson.org/sumexp22/1009/thumbnail.jp

Mechanism of Selective VEGF-A Binding by Neuropilin-1 Reveals a Basis for Specific Ligand Inhibition

Neuropilin (Nrp) receptors function as essential cell surface receptors for the Vascular Endothelial Growth Factor (VEGF) family of proangiogenic cytokines and the semaphorin 3 (Sema3) family of axon guidance molecules. There are two Nrp homologues, Nrp1 and Nrp2, which bind to both overlapping and distinct members of the VEGF and Sema3 family of molecules. Nrp1 specifically binds the VEGF-A164/5 isoform, which is essential for developmental angiogenesis. We demonstrate that VEGF-A specific binding is governed by Nrp1 residues in the b1 coagulation factor domain surrounding the invariant Nrp C-terminal arginine binding pocket. Further, we show that Sema3F does not display the Nrp-specific binding to the b1 domain seen with VEGF-A. Engineered soluble Nrp receptor fragments that selectively sequester ligands from the active signaling complex are an attractive modality for selectively blocking the angiogenic and chemorepulsive functions of Nrp ligands. Utilizing the information on Nrp ligand binding specificity, we demonstrate Nrp constructs that specifically sequester Sema3 in the presence of VEGF-A. This establishes that unique mechanisms are used by Nrp receptors to mediate specific ligand binding and that these differences can be exploited to engineer soluble Nrp receptors with specificity for Sema3

Plasma Concentrations of Trace Elements Selenium and Cobalt During and After Coronary Artery Bypass Grafting Surgery

Trace elements selenium (Se) and cobalt (Co) are essential in the human body, and a correlation between Se and cardiac surgery has been suggested. We investigated the plasma concentrations of Se and Co during and after coronary artery bypass grafting (CABG) surgery under cardiopulmonary bypass (CPB). From December 2019 to January 2020, preoperative plasma samples from isolated first-time CABG patients (n=20; 10 males, 10 females) were prospectively collected post-anesthesia and before CPB (T1), 45 min after CPB started (T2), 90 min after CPB started (T3), and postoperative days 1 (T4), and day 4 (T5). The plasma concentrations of Se and Co were measured. The Se concentration was significantly decreased at T2 (105.24±4.08 vs. 68.56±2.42 μg/L, p<0.001) and T3 (105.24±4.08 vs. 80.41±3.40 μg/L, p<0.001). The Co concentration was significantly decreased at T4 (0.35±0.19 vs. 0.26±0.13 μg/L, p<0.01) and T5 (0.35±0.19 vs. 0.23±0.11 μg/L, p<0.001). Five patients developed atrial fibrillation (AF); there was no other operative mortality or major morbidity. This is the first report of alterations of plasma Se and Co concentrations during and after CABG surgery. Our results may indicate that Se supplementation before or during CABG and Co supplementation after CABG may become necessary for patients undergoing CABG

Guanxintai Exerts Protective Effects on Ischemic Cardiomyocytes by Mitigating Oxidative Stress

Oxidative stress participates in numerous myocardial pathophysiological processes and is considered a therapeutic target for myocardial ischemia and heart failure. Guanxintai (GXT), a traditional Chinese medicine, is commonly used to treat cardiovascular disease on account of its numerous beneficial physiological activities, such as dilating coronary arteries, inhibiting platelet aggregation, and reducing the serum lipid content. However, the antioxidative properties of GXT and potential underlying mechanisms remain to be established. In the present study, we investigated the protective effects of GXT on ischemic cardiomyocytes and the associated antioxidative mechanisms, both in vivo and in vitro. Notably, GXT treatment reduced the degree of cardiomyocyte injury, myocardial apoptosis, and fibrosis and partially improved cardiac function after myocardial infarction. Furthermore, GXT suppressed the level of ROS as well as expression of NADPH oxidase (NOX) and phospho-p38 mitogen-activated protein kinase (MAPK) proteins. Our results collectively suggest that the protective effects of GXT on ischemic cardiomyocytes are exerted through its antioxidative activity of NOX inhibition

catena-Poly[zinc(II)-bis­[μ2-3-(3-pyrid­yl)­benzoato]-κ2 O:N;κ2 N:O]

In the title compound, [Zn(C12H8NO2)2]n, the Zn2+ cation is coordinated by a pair of carboxyl­ate O atoms as well as two pyridyl N atoms to afford a distorted tetra­hedral environment. Adjacent Zn2+ cations, with a separation of 8.807 (2) Å, are linked by two 3-(3-pyrid­yl)benzoate ligand bridges, generating an infinite ribbon extending parallel to [001]

RELATIONSHIP BETWEEN THE KINETIC POWER AND BOLOMETRIC LUMINOSITY OF JETS: LIMITATION FROM BLACK HOLE X-RAY BINARIES, ACTIVE GALACTIC NUCLEI, AND GAMMA-RAY BURSTS

Natural Science Foundation of China [11333004, 11203057, 11133005, 11233006, 11103059, 11103061, 11121062]; CAS/SAFEA International Partnership Program for Creative Research Teams; Natural Science Foundation of Fujian Province [2011J01023]The correlation between the kinetic power P-jet and intrinsic bolometric luminosity L-jet of jets may reveal the underlying jet physics in various black hole systems. Based on the recent work by Nemmen et al., we re-investigate this correlation with additional sources of black hole X-ray binaries (BXBs) in hard/quiescent states and low-luminosity active galactic nuclei (LLAGNs). The new sample includes 29 sets of data from 7 BXBs and 20 LLAGNs, with P-jet and L-jet being derived from spectral modeling of the quasi-simultaneous multi-band spectra under the accretion jet scenario. Compared to previous works, the range of luminosity is now enlarged to more than 20 decades, i.e., from similar to 10(31) erg s(-1) to similar to 10(52) erg s(-1), which allows for better constraining of the correlation. One notable result is that the jets in BXBs and LLAGNs almost follow the same P-jet-L-jet correlation that was obtained from blazars and gamma-ray bursts. The slope indices we derived are 1.03+/-0.01 for the whole sample, 0.85+/-0.06 for the BXB subsample, 0.71+/-0.11 for the LLAGN subsample, and 1.01+/-0.05 for the LLAGN-blazar subsample, respectively. The correlation index around unit implies the independence of jet efficiency on the luminosity or kinetic power. Our results may further support the hypothesis that similar physical processes exist in the jets of various black hole systems

First identification of long non-coding RNAs in fungal parasite Nosema ceranae

International audienceAbstractNosema ceranae is a unicellular fungal parasite of honey bees and causes huge losses for apiculture. Until present, no study on N. ceranae long non-coding RNAs (lncRNAs) was documented. Here, we sequenced purified spores of N. ceranae using strand-specific library construction and high-throughput RNA sequencing technologies. In total, 83 novel lncRNAs were predicted from N. ceranae spore samples, including lncRNAs, long intergenic non-coding RNAs (lincRNAs), and sense lncRNAs. Moreover, these lncRNAs share similar characteristics with those identified in mammals and plants, such as shorter length and fewer exon number and transcript isoforms than protein-coding genes. Finally, the expression of 12 lncRNAs was confirmed with RT-PCR, confirming their true existence. To our knowledge, this is the first evidence of lncRNAs produced by a microsporidia species, offering novel insights into basic biology such as regulation of gene expression of this widespread taxonomic group